Trisazo dye and dye composition containing the same

ABSTRACT

The present invention provides a trisazo dye represented by the formula: ##STR1## [wherein A is a phenyl group substituted with at least one substituent selected from the group consisting of an amino group, a substituted amino group and a hydroxyl group, B is a substituted or non-substituted phenyl group, X is a group of the formula: ##STR2## Q is a group of the formula: ##STR3## (wherein n is 1 or 2), and M is hydrogen, alkali metal, aliphatic alkyl ammonium or alkanol ammonium]. An aqueous ink composition and a process for the producing a concentrated solution containing the trisazo dye are also disclosed.

FIELD OF THE INVENTION

The present invention relates to a novel trisazo dye. More particularly,it relates to an aqueous ink composition containing the trisazo dye anda process for producing a concentrated solution containing the trisazodye.

BACKGROUND OF THE INVENTION

Heretofore, as a writing ink or jet printing ink used for recording onmaterials to be recorded (e.g. paper, etc.) or an ink for dyeing fibers,hides and the like, various polyazo dyes have been employed.

The polyazo dye consists mainly of a direct dye and, therefore, thedyeing process is simple and fastness is comparatively excellent.Polyazo dyes having such advantages are widely employed in the industry.

However, regarding the polyazo dye, there are problems to be solved.Firstly, there is a problem as to chemical properties, because excellentchemical properties such as stable solubility of dye, stability ofconcentrated dye solution with time and stability of dye density withtime are required for dyes which are sued for writing inks.

Secondly, there is a problem of safety, because safety of chemicalsubstances has recently been noted and dyes having excellent safety andwhich have no bad influences upon a human body are required.

As dyes wherein dyeing properties and fastness are improved, forexample, benzidine or benzidine derivative based black trisazo dyes orpolyazo dyes (e.g. C.I. Direct Black 19, C.I. Direct Black 154, C.I.Direct Black 168, etc.) have been widely used. However, these dyes posequestion about safety for the human body because the Ames test givesfalse positive or positive results.

On the other hand, useful as polyazo black dyes wherein safety forhumans is improved, are for example, food colors (e.g. recordingsolution wherein Food Black 2 is used as a recording agent, etc.),4,4'-diaminodiphenylamine-2-sulfonic acid (substituent for benzidine)based trisazo dyes, stilbene tetrakisazo dyes having no amino group intheir molecular structure and the like. However, aqueous inks whereinthese dyes are used have poor water and light resistance of writing and,therefore, dyeing properties and fastness are inferior.

Polyazo dyes which satisfy the above properties have never beenobtained.

Further, a water-soluble dye can be separated from aqueous systems bymeans such as aciding-out, salting out and the like. However, it isdifficult to obtain a dye having high purity because of inclusion of aninorganic salts upon separation, whereby, various problems are caused.For example, when a dye having low purity is used for an aqueous writingink, there is a disadvantage in that the ink is not consistently fed toa pen point. Also, when a dye of low purity is used for a jet printingink, clogging of outlet orifice may occur.

OBJECTS OF THE INVENTION

One object of the present invention is to provide a trisazo dye havingexcellent chemical properties (e.g. dyeing properties, fastness, hue,solubility, etc.) and safety.

Another object of the present invention is to provide an aqueous inkcomposition containing the trisazo dye.

Still another object of the present invention is to provide a processfor producing a highly purified trisazo dye concentrated solution.

These objects as well as other objects and advantages of the presentinvention will become apparent to those skilled in the art from thefollowing description with reference to the following drawings.

BRIEF EXPLANATION OF DRAWINGS

FIG. 1 is a graph illustrating a visible spectrum of a trisazo dye ofone embodiment of the present invention.

FIG. 2 is a graph illustrating a visible spectrum of a trisazo dye ofanother embodiment of the present invention.

FIG. 3 is a graph illustrating a liquid chromatography of a trisazo dyeof one embodiment of the present invention.

FIG. 4 is a graph illustrating a liquid chromatography of a trisazo dyeof another embodiment of the present invention.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a trisazo dyerepresented by the formula: ##STR4## wherein A is a phenyl groupsubstituted with at least substituent selected from the group consistingof an amino group, a substituted amino group and a hydroxyl group, B isa substituted or non-substituted phenyl group, X is a group of theformula: ##STR5## wherein n is 1 or 2, and M is hydrogen, alkali metal,aliphatic alkyl ammonium or alkanol ammonium], an aqueous inkcomposition containing the trisazo dye and a process for producing aconcentrated solution containing the trisazo dye.

DETAILED DESCRIPTION OF THE INVENTION

The trisazo dye of the present invention is an azo dye having a bondgroup of the formula: ##STR6## which is introduced into a molecularstructure by tetrazotization of 1,4-bis(4-aminophenoxy)benzene or1,3-(4-aminophenoxy)benzene.

The dye of the formula (I) of the present invention is obtained by aprocess including the steps of:

tetrazotizing 1,4-bis(4-aminophenoxy)benzene or1,3-(4-aminophenoxy)benzene (1 mol) of the formula: ##STR7## wherein Ris as defined above, by a normal method to obtain a tetrazonium salt(step 1);

adding an aqueous solution containing 1 mol of a compound of theformula: ##STR8## (e.g. 1-amino-8-naphthol-3,6-disulfonic acid, etc.) tothe resulting tetrazotized solution to conduct coupling (step 2);

adding a diazotized diazo component B (1 mol) to the reaction solutionto obtain a disazo dye (step 3);

adding a coupling component A (1 mol) to the reaction solution toconduct coupling to obtain a trisazo dye (step 4); and

concentrating and purifying the resulting reaction solution (step 5).

The reactions or operation conditions used in the above steps 1 to 5areknown to the art.

Preferred examples of the diamino compound used in the step 1 include1,4'-bis(4-aminophenoxy)benzene and 1,3-bis(4-aminophenoxy)benzene.

Preferred examples of the coupling component used in the step 2 inlcude1-amino-8-naphthol-3,6-disulfonic acid (hereinafter referred to as "Hacid"), 1-amino-8-naphthol-4,6-disulfonic acid (hereinafter referred toas "K acid"), 1-amino-8-naphthol-4-sulfonic acid (hereinafter referredto as "S acid"), 4-amino-8-naphthol-6-sulfonic acid (hereinafterreferred to as "M acid "), 3-amino-8-naphthol-6-sulfonic acid(hereinafter referred to as "J acid"), 2-amino-8-naphthol-6-sulfonicacid (hereinafter referred to as "γacid") and the like. It is preferredto use H acid, K acid, S acid and J acid, particularly H acid.

Preferred examples of the diazo component B used in the step 3 includenon-substituted or substituted anilines, e.g. aniline, o-, m- andp-toluidine, o-, m- and p-xylidine, anisidine, cresidine,p-nitroaniline, p-chloroaniline, ethylaniline, p-(sec-butyl)aniline,etc. and aminobenzene derivatives such as aminobenzenesulfonic acids,e.g. orthanilic acid, methanilic, sulfanilic acid, etc. It isparticularly preferred to use aniline, sulfanilic acid andp-(t-butyl)aniline.

Preferred example of the coupling component A used in the step 4 includephenol derivatives, e.g. o-, m- and p-aminophenol, resorcin, catechol,cresol, 4-t-butylphenol, 4-hydroxyanisole, chlorophenol,acetylaminophenol, etc.), N,N-diethylaniline, N-(β-oxyethyl)aniline andN,N-di(β-oxyethyl)aniline. It is particularly preferred to usem-aminophenol and resorcin.

The trisazo dye of the present invention thus obtained has the samelight resistance as that of a benzidine or tolidine azo dye as well asexcellent water resistance (water resistance of writing) in comparisonwith the above azo dye, and is superior in solubility in an aqueousmedium. Further, the trisazo dye of the present invention is a nontoxictrisazo dye which gives negative results in a back mutation test usingan organism, which is generally known as a test method for evaluatingtoxicity, i.e. AMES test (mutation test).

The sulfonic group in the trisazo dye of the present invention can beconverted into an alkali metal or ammonium salt, like several azo dyeshaving the sulfonic group. Further, it can also be converted into anamine salt with fatty amine or alkanolamine.

As the amine used for preparing the trisazo dye of the presentinvention, for example, there are aliphatic amines, e.g., butylamine,dibutylamine, sec-butylamine, di-t-butylamine, n-, iso-, sec- andt-amylamine, hexylamine, pentylamine, octylamine, 2-ethylhexylamine,di-(2-ethylhexyl)amine, dodecylamine, etc.; alicyclic amines, e.g.cyclohexylamine, di-cyclohexylamine, etc.; alkoxyalkylamines, e.g.3-ethoxypropylamine, di-(3-ethoxypropyl)amine, 3-butoxypropylamine,octooxypropylamine, 3-(2-ethylhexyloxy)propylamine, etc.; alkanolgroup-containing amines, (e.g. ethanolamine, diethanolamine,triethanolamine, N-cyclohexyl-N-ethanolamine, N-dodecylimino-di-ethanol,etc. and the like.

By converting the sulfonic group in the trisazo dye of the presentinvention into an amine salt, a water-soluble or alcohol-soluble dye canbe prepared depending upon the kind of the above basic compound.

In the preferred embodiment of the present invention, a reverse osmosismethod is used in step 5 of concentrating and purifying a solution whichcontains the trisazo dye of present invention obtained in the steps 1 to4. By the concentration/purification step, the conventional problemwhich is caused by inclusion of impurities upon separation of thewater-soluble dye is solved.

The reverse osmosis method is a concentration method employing aphenomenon wherein a solvent is transferred through a semipermeablemembrane from a concentrated solution side to a dilute solution side byapplying a pressure larger than the osmotic pressure to the concentratedsolution side which is partitioned from a dilute solution by thesemipermeable membrane.

Preferred examples of the semipermeable membrane used in theconcentration/purification step include reverse osmosis membranes (e.g.acetylcellusole membrane, synthesized high polymeric composite membrane,chargeable synthesized polymeric composite membrane, etc.).

The concentration/purification step in the present invention isconducted by cycling a reaction solution containing trisazo dye of thepresent invention obtained in the steps 1 to 4 while applying a pressureof about 4 to 8 Kgf/cm² to one side of a pressure resistant acrylicvessel which is partitioned by the semi-permeable membrane, until theconductivity of permeated water becomes 1 μs or less.

According to the concentration/purification step using the reverseosmosis method, the concentration of the dye solution is optionallycontrolled to 10 to 20% by weight. The concentrated solution of the dyethus obtained has high purity and is stable for a long period of time.Preferably, the concentrated solution of the present invention is atrisazo dye solution, which comprises 15% by weight of a trisazo dye ofthe formula (I) and 85% by weight of a medium (water).

The present invention also provides an aqueous ink compositioncomprising a trisazo dye of the formula (I) and an aqueous medium.

As the preferred examples of the aqueous organic solvent used for theaqueous ink composition of the present invention, for example, there arelower alcohols such as monovalent alcohols e.g., ethanol, n-propanol,iso-propanol, n-butanol, diacetone alcohol, etc.; monoalkyl ethers ofdiols, e.g. ethylene glycol monomethyl ether, ethylene glycol monoethylether, propylene glycol monoethyl ether, diethylene glycol monoethylether, diethylene glycol monobutyl ether, dipropylene glycol monoethylether, etc.; monoacetates of diols, e.g. ethylene glycol monoacetate,polypropylene glycol monoacetate, etc.; benzyl alcohol; cyclohexanol;divalent alcohols, e.g., glycols such as ethylene glycol, diethyleneglycol, trimethylene glycol, triethylene glycol, tetraethylene glycol,polyethylene glycol, propylene glycol, butanediol, etc.; trivalentalcohols, e.g. glycerin, trimethylolpropane, 1,2,6-hexanetriol, etc.;dioxane; N-methyl-2-pyrrolidone; ethyl lactate and the like. It isparticularly preferred to use low toxic or nontoxic iso-propanol,ethylene glycol, propylene glycol monoalkyl ether,N-methyl-2-pyrrolidone and the like.

The preferred amount of the organic solvent in the aqueous inkcomposition of the present invention is 5 to 95% by weight, preferably10 to 80% by weight, more preferably 15 to 30% by weight, based on thetotal weight of the ink composition.

The amount of the trisazo dye in the aqueous ink varies depending uponthe application of the ink and is not specifically limited. It ispreferred that the amount is generally 5 to 10% by weight for aball-point pen, 5 to 15% by weight for a marking pen and 3 to 10% byweight for a jet recording ink.

According to the purpose to be included, there can be used a suitableamount of additives which are normally used, for example, water-solubleresins (e.g. low condensate of vinyl pyrrolidione, water-soluble alkydresin, water-soluble acrylic resin, etc.), alcohol-soluble resins (e.g.alcohol-soluble phenol resin, acrylic resin, styrene maleic resin,ketone resin, etc.), preservatives, pH adjustors, surfactants and thelike.

The aqueous ink composition of the present invention thus obtained canbe used for various inks having excellent dissolution stability andstability in addition to writing ink and jet recording solution, and theresulting writing thereof has good fastness. Further, when the aqueoussolution of the trisazo dye obtained by the process of the presentinvention is used for dyeing cellulose fibers or hides, build-upproperty is excellent and fast dyeing can be conducted.

The following Examples and Comparative Examples further illustrate thepresent invention in detail but are not construed to limit the scopethereof. In the Examples and Comparative Examples, all "parts" are byweight unless otherwise stated.

EXAMPLE 1

1,3-Bis(4-aminophenoxy)benzene (29.3 parts, 0.1 mols) was dissolved inconcentrated hydrochloric acid (25 parts) and water (150 parts) withheating and the mixture was tetrazotized by adding a 36% aqueoussolution of sodium nitrite (42.5 parts, 0.2 mols) at 0° C. To theresulting tetrazotized solution was added an aqueous solution of H acid(36.4 parts, 0.1 mols), followed by stirring at 5° to 10° C. for 2.5hours. Thereafter, this solution was adjusted to pH 3.6 to 4.0 with a10% aqueous solution of sodium carbonate, followed by additionalstirring at 5° to 15° C. for 17 hours. Then, this solution was adjustedto pH 8.3 to 8.6 with a 20% solution of sodium carbonate. A solution ofaniline (9.3 parts, 0.1 mols) as a diazo component B which wasdiazotized in advance was added to the solution and stirred at 5° to 15°C. for 5 hours. Then, a solution obtained by dissolving m-aminophenol(10.9 parts, 0.1 mols) into water (150 parts) was further added to thesolution and stirred overnight to complete the reaction.

The resulting dye-containing solution was concentrated and purifiedusing a chargeable synthesized polymeric composite membrane (trade nameof "NTR7410", manufactured by Nitto Denko Co.) as a reverse osmosismembrane according to a reverse osmosis method comprising pressing adye-containing solution side at a pressure of about 4 to 8 Kgf/cm² toobtain a concentrated dye solution.

The concentrated solution containing the trisazo dye thus obtained wasconcentrated and dried to obtain 89 g of a black dye. By highperformance liquid chromatography (HPLC) and visible absorption spectrumanalysis, it was confirmed that the resulting dye is a dye having astructure of the following formula. A maximum absorption wavelength (nm)of a visible absorption spectrum of the dye solution and hue of the dyeare also shown. ##STR9##

λ_(max) (nm): 438, 586; Greenish black color

The evaluation results of writing of the dye are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2. Further, avisible spectrum is shown in FIG. 1 and a liquid chromatography is shownin FIG. 3.

Liquid chromatography analysis was conducted under the followingconditions.

1. Column: NUCLEOSIL 10C8 4.0*200 mm

2. Carrier;

    ______________________________________                                        Transfer phase                                                                (Solution A)  CH.sub.3 CN   10      ml                                                      H.sub.2 O     90      ml                                                      CH.sub.3 COOH 20      μl                                                   KH.sub.2 PO.sub.4                                                                           0.02    N                                         (Solution B)  CH.sub.3 CN   10      ml                                                      H.sub.2 O     90      ml                                        Gradient condition                                                            Initial condition                                                                           →      Final condition                                   Solution A 80%                                                                              25 min.       Solution B 20%                                    Solution B 20%              Solution A 80%                                    ______________________________________                                    

3. Flow rate: 1.5 ml/min.

4. Column temperature: 45° C.

5. Sensing wavelength: 600 nm

6. Preparation of sample:

A concentrated solution (200 μl) was dissolved in DMF (5 ml) and theresulting solution (200 μl) was dissolved in a carrier solution (5 ml)to obtain a sample solution for analysis. By using this sample solution(10 μl), analysis was conducted.

EXAMPLES 2 AND 3

According to the same manner as that described in Example 1 except forusing components A and B shown in Table. 1 in place of aniline as adiazo component B and m-aminophenol as a coupling component A, dyes ofExamples 2 and 3 were obtained. Analysis was conducted according to thesame manner as that described in Example 1. It was confirmed that theresulting dye has a structure of the following formula, respectively. Amaximum absorption wavelength (nm) of a visible absorption spectrum ofthe dye solution and hue of the dye are also shown. ##STR10##

λ_(max) (nm): 438, 586; Greenish black color ##STR11##

λ_(max) (nm): 438, 586; Greenish black color

The evaluation results of writing of the dyes are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2.

EXAMPLE 4

According to the same manner as that described in Example 1 except forusing 1,4-bis(4-aminophenoxy)benzene (0.1 mols) in place of1,3-bis(4-aminophenoxy)benzene (0.1 mols), a concentrated dye solutionwas obtained.

A dye content was concentrated and dried from the obtained concentratedsolution containing a trisazo dye to obtain a black dye (80 g). Analysiswas conducted according to the same manner as that described inExample 1. It was confirmed that the dye has a structure of thefollowing formula. A maximum absorption wavelength (nm) of a visibleabsorption spectrum and hue of the dye are also shown. ##STR12##

λ_(max) (nm): 438, 588; Greenish black color

The evaluation results of writing of the dye are shown in Table 1 andthose of Ames test are shown in Table. 1 and Table. 2. A visiblespectrum of the dye is shown in FIG. 2.

EXAMPLE 5 TO 8

According to the same manner as that described in Example 4 except forusing components B and A shown in Table. 1 in place of aniline as adiazo component B and m-aminophenyl as a component A, dyes of Example 5to 8 were obtained. Analysis was conducted according to the same manneras that described in Example 1. It was confirmed that the resulting dyeshave a structure of the following formula, respectively. A maximumabsorption wavelength (nm) of a visible absorption spectrum and hue ofthe dye are also shown. ##STR13##

λ_(max) (nm); 438, 588; Greenish black color ##STR14##

λ_(max) (nm): 438, 588; Greenish black color ##STR15##

λ_(max) (nm): 438, 588; Greenish black color ##STR16##

λ_(max) (nm): 438, 588; Greenish black color

The evaluation results of writing of each dye are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2.

EXAMPLE 9

According to the same manner as that described in Example 1 except forusing K acid in place of H acid, a dye was obtained. Analysis wasconducted according to the same manner as that described in Example 1.It was confirmed that the resulting dye has a structure of the followingformula. A maximum absorption wavelength (nm) of a visible absorptionspectrum and hue of the dye are also shown. ##STR17##

λ_(max) (nm): 438, 586; Greenish black color

The evaluation results of writing of the dye are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2.

EXAMPLES 10 AND 11

According to the same manner as that described in Example 5 except forusing S acid and J acid in place of H acid, dyes of Examples 10 and 11were obtained. Analysis was conducted according to the same manner asthat described in Example 1. It was confirmed that the resulting dye hasa structure of the following formula, respectively. A maximum absorptionwavelength (nm) of a visible absorption spectrum and hue of the dye arealso shown. ##STR18##

λ_(max) (nm): 438, 586; Greenish black color ##STR19##

λ_(max) (nm): 438, 580; Greenish black color

The evaluation results of writing of each dye are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2.

COMPARATIVE EXAMPLES 1 TO 3

According to the same manner as that described in Example 1 except forusing aromatic diamines and components B and A shown in Table. 1 inplace of aniline as a disazo component B and m-aminophenol as a couplingcomponent A, dyes of Comparative Examples 1 to 3 were obtained. Analysiswas conducted according to the same manner as that described inExample 1. It was confirmed that the resulting dyes have each structureof the following formula, respectively. Hue is also shown. ##STR20##

The evaluation results of writing of each dye are shown in Table. 1 andthose of Ames test are shown in Table. 1 and Table. 2.

EVALUATION METHOD OF WRITING

Light resistance: The resulting dye was dissolved in a 5% aqueousdiethylene glycol solution to obtain a 3% dye solution. The solution wasextended over a writing paper A (JIS P-3201) with an applicator (25μ) toform a drawndown paper, which was exposed to sunlight for one month. Adegree of discoloration was compared with that before testing.

Water resistance: The drawndown paper was air-dried for one day anddipped in tap water. Then, a deflection density was measured by aMacbeth densitometer (manufactured by Colmorgen Co. as TR-927) tocompare with that before testing.

EVALUATION CRITERIA

Light resistance:

A: Little discoloration is observed.

B: Discoloration is observed.

C: Discoloration is severe.

Water resistance:

A: Reflection density is more than 70% of that before testing.

B: Reflection density is 50 to 70% of that before testing.

C: Reflection density is less than 50% that before testing.

EVALUATION METHOD OF AMES TEST

Regarding various specimen solutions respectively containing trisazodyes obtained in Examples 1 to 11 to the present invention and dyes ofComparative Examples 1 to 3, the number of mutant colonies wasdetermined using strains TA98. A ratio of the number of coloniesdetermined by Ames test to a control was shown in Table. 2. When theratio is less than 2, it is "negative" and, when the ratio is more than2, it is "positive", and the results are shown in Table. 1.

In Table. 2, the column (-) shows the ratio when no drug metabolicactive enzyme S-9 is added, and the column (+) shows the ratio when adrug metabolic active enzyme S-9 is added.

    ______________________________________                                        Component         Amount (parts by weight)                                    ______________________________________                                        Deionized water   35                                                          Propylene glycol  15                                                          Concentrated solution                                                                           50                                                          of Example 1                                                                  Surfactant (Unidine DS-401)                                                                     1                                                           Preservative      0.1                                                         ______________________________________                                    

A black ink for an aqueous ball point pen was made according to theabove formulation and a writing performance was examined. Smooth writingwas available for a long period of time, and light and water resistanceof writing was excellent.

EXAMPLE 13

    ______________________________________                                        Component       Amount (parts by weight)                                      ______________________________________                                        Deionized water 35                                                            Ethylene glycol 10                                                            Diethylene glycol                                                                             5                                                             Concentrated solution                                                                         50                                                            of Example 3                                                                  Preservative    0.2                                                           ______________________________________                                    

A black ink for a marking pen was made according to the aboveformulation and a writing performance was examined. Smooth writing wasavailable for a long period of time, and light and water resistance ofwriting was excellent.

EXAMPLE 14

    ______________________________________                                        Component       Amount (parts by weight)                                      ______________________________________                                        Deionized water 70                                                            Diethylene glycol                                                                             10                                                            Sodium benzoate 0.1                                                           Concentrated solution                                                                         20                                                            of Example 7                                                                  ______________________________________                                    

A black jet recording ink was made according to the above formulationand a recording performance was examined using a commercially availableink-jet printer. Printing could be conducted without clogging oforifice, and light and water resistance of the recorded literature/imagewas excellent.

STABILITY OF CONCENTRATED SOLUTION WITH TIME

Each concentrated solution obtained in Examples 1 to 8 was charged in a50 ml glass sample bottle, respectively. Then, stability with time wasevaluated, using an incubator (manufactured by Sanyo Denki Co.). In atest (temperature range: -5° to 50° C.; repeat time: 60 minutes; testperiod: 3 months), precipitation of the dye and change of properties ofthe concentrated solution were not observed.

                                      TABLE 1                                     __________________________________________________________________________               Novel trisazo dye  Writing evaluation                                         Aromatic           Water                                                                              Light                                      Component A                                                                              diamines                                                                           Component B                                                                          Component C                                                                          resistance                                                                         resistance                                                                         AMES evaluation                       __________________________________________________________________________    Ex. 1                                                                             m-Amino                                                                              *1   Aniline                                                                              H acid A    B    Negative                                  phenol                                                                    Ex. 2                                                                             Resorcin                                                                             *1   Aniline                                                                              H acid B    B    Negative                              Ex. 3                                                                             Resorcin                                                                             *2   p sec  H acid A    B    Negative                                              Butylaniline                                                  Ex. 4                                                                             m-Amino                                                                              *1   Aniline                                                                              H acid A    B    Negative                                  phenol                                                                    Ex. 5                                                                             Resorcin                                                                             *2   Aniline                                                                              H acid B    B    Negative                              Ex. 6                                                                             Resorcin                                                                             *2   p-sec- H acid A    B    Negative                                              Butylaniline                                                  Ex. 7                                                                             Resorcin                                                                             *2   o-Toluidine                                                                          H acid A    B    Negative                              Ex. 8                                                                             m-Amino                                                                              *2   Sulfanilic                                                                           H acid B    B    Negative                                  phenol      acid                                                          Ex. 9                                                                             m-Amino                                                                              *1   Aniline                                                                              K acid A    B    Negative                                  phenol                                                                    Ex. 10                                                                            Resorcin                                                                             *2   Aniline                                                                              S acid A    B    Negative                              Ex. 11                                                                            Resorcin                                                                             *2   Aniline                                                                              J acid A    B    Negative                              Comp.                                                                             m-Phenylene                                                                          *3   Aniline                                                                              H acid B    B    Positive                              Ex. 1                                                                             diamine                                                                   Comp.                                                                             m-Amino                                                                              *4   Aniline                                                                              H acid C    B    Positive                              Ex. 2                                                                             phenol                                                                    Comp.                                                                             Resorcin                                                                             *3   Sulfanilic                                                                           H acid C    B    Positive                              Ex. 3           acid                                                          __________________________________________________________________________     *1: 1,3Bis(4-aminophenoxy)benzene                                             *2: 1,4Bis(4-aminophenoxy)benzene                                             *3: oTolidine                                                                 *4: Diaminodiphenylsulfone                                               

                  TABLE 2                                                         ______________________________________                                        Ames test results                                                                    Concentration of substance to be                                              tested (μg/plate)                                                          S 9  20       78     313    1250 5000                                  ______________________________________                                        Ex. 1    -      0.76     0.86 0.86   0.76 0.71                                         +      1.13     0.94 1.06   0.53 0.59                                Ex. 2    -      1.07     1.20 1.02   1.16 1.28                                         +      1.34     1.19 1.39   1.28 1.27                                Ex. 3    -      0.76     0.86 0.86   1.10 0.95                                         +      1.32     1.79 1.59   0.76 0.56                                Ex. 4    -      0.88     0.79 0.96   1.15 0.92                                         +      1.04     1.23 0.99   0.88 0.90                                Ex. 5    -      0.89     0.95 0.63   0.79 0.68                                         +      0.93     1.04 0.86   1.04 0.57                                Ex. 6    -      1.01     1.04 1.16   0.97 0.91                                         +      1.01     1.00 0.98   0.84 0.84                                Ex. 7    -      0.95     1.00 0.80   0.80 1.00                                         +      0.94     0.89 1.00   1.05 1.05                                Ex. 8    -      1.05     1.08 0.93   1.03 1.12                                         +      0.94     0.92 0.92   0.93 1.03                                Ex. 9    -      0.85     0.65 0.75   0.60 1.15                                         +      1.05     1.00 1.16   1.00 0.53                                Ex. 10   -      1.03     1.01 0.84   1.02 0.97                                         +      0.91     0.92 0.85   1.09 0.90                                Ex. 11   -      0.96     1.00 0.81   1.04 1.35                                         +      1.25     1.64 1.34   0.64 1.07                                Comp.    -      0.72     0.68 0.84   0.76 0.96                                Ex. 1    +      1.92     2.35 2.50   1.50 0.85                                Comp.    -      1.10     1.52 1.29   1.38 3.38                                Ex. 2    +      5.26     26.3 9.11   1.23 1.61                                Comp.    -      0.92     1.00 2.56   3.56 0.96                                Ex. 3    +      1.20     2.24 4.16   1.12 0.16                                ______________________________________                                    

What is claimed is:
 1. A trisazo dye represented by the formula:##STR21## wherein A is a phenyl group substituted with at least onesubstituent selected from the group consisting of an amino group, asubstituted amino group and a hydroxyl group, B is a substituted ornon-substituted phenyl group, X is a group of the formula: ##STR22## Qis a group of the formula: ##STR23## wherein n is 1 or 2, and M ishydrogen, alkali metal, aliphatic alkyl ammonium or alkanol ammonium. 2.An aqueous ink composition which comprises the trisazo dye according toclaim 1 and an aqueous medium.
 3. A trisazo dye according to claim 1 ofthe formula: ##STR24##
 4. A trisazo dye according to claim 1, of theformula: ##STR25##
 5. A trisazo dye according to claim 1, of theformula: ##STR26##
 6. A trisazo dye according to claim 1, of theformula: ##STR27##
 7. A trisazo dye according to claim 1, of theformula: ##STR28##
 8. A trisazo dye according to claim 1, of theformula: ##STR29##
 9. A trisazo dye according to claim 1, of theformula: ##STR30##
 10. A trisazo dye according to claim 1, of theformula: ##STR31##
 11. A trisazo dye according to claim 1, of theformula: ##STR32##
 12. A trisazo dye according to claim 1, of theformula: ##STR33##
 13. A trisazo dye according to claim 1, of theformula: ##STR34##
 14. The aqueous ink composition according to claim 2,wherein said trisazo dye is present at a level of 3-15% by weight. 15.The aqueous ink composition according to claim 12, wherein said trisazodye is present at a level of about 5-10% by weight.
 16. The aqueous inkcomposition according to claim 2, wherein said aqueous medium compriseswater and an aqueous organic solvent.
 17. The aqueous ink compositionaccording to claim 16, wherein said aqueous organic solvent is selectedfrom the group consisting of monovalent alcohols, divalent alcohols,trivalent alcohols, monoalkyl ethers of diols and monoacetates of diols.18. The aqueous ink composition according to claim 16, wherein saidaqueous organic solvent is selected from the group consisting ofiso-propanol, ethylene glycol, propylene glycol monoalkyl ether,N-methyl-2-pyrrolidone, ethyllactate and dioxane.
 19. The aqueous inkcomposition according to claim 17, wherein said monovalent alcohol isselected from the group consisting of ethanol, n-propanol, iso-propanol,n-butanol, diacetone alcohol, benzyl alcohol and cyclohexanol.
 20. Theaqueous ink composition according to claim 17, wherein said divalentalcohol is selected from the group consisting of ethylene glycol,diethylene glycol, trimethylene glycol, triethylene glycol,tetraethylene glycol, polyethylene glycol, propylene glycol and butanediol.
 21. The aqueous ink composition according to claim 16, whereinsaid trivalent alcohol is selected from the group consisting ofglycerin, trimethylolpropane and 1,2,6-hexanetriol.
 22. The aqueous inkcomposition according to claim 17, wherein said monoalkylether of a diolis selected from the group consisting of ethylene glycol monomethylether, ethylene glycol monoethyl ether, propylene glycol monoethylether, diethylene glycol monoethyl ether, diethylene glycol monobutylether and dipropylene glycol monoethyl ether.
 23. The aqueous inkcomposition according to claim 17, wherein said monoacetate of a diol isselected from the group consisting of ethylene glycol monoacetate andpropylene glycol monoacetate.
 24. The aqueous ink composition accordingto claim 16, wherein said aqueous organic solvent is present in anamount of 5-95% by weight.